The advantages of using phased array or multi-coil MR coil systems to enhance magnetic resonance imaging and spectroscopy are well known. A situation facing the designer of such coils is the finite number of available simultaneous data acquisition channels in the host MR system; frequently, there are only four available channels, sometimes known as receivers, in the host system.
Another issue is the reconstruction time to create the images from the collected data; processing multiple channels to form a single image increases the time needed by the magnetic resonance imaging system to process the data, by two or three dimensional Fourier Transform techniques or other methods, to create the final images. Another consideration is the fact that data acquisition hardware with additional performance capabilities may only be available on one receiver, or on fewer than the total number of available receivers.
Reconstruction of an image from two quadrature modes of a specific phased array coil element via two separate data acquisition channels [or receivers] provides the best possible image signal to noise ratio and uniformity, since the data can always be reconstructed in the most optimum way. However, the use of two separate receivers for the two quadrature signals from a specific phased array coil element may cause problems with reconstruction time, or limitations due to the finite number of available receivers. Thus, there may be conditions when combining the two quadrature signals at the RF level into a single signal may be most advantageous, and other times when processing the two RF signals independently via two separate data acquisition receivers may be the best scheme.
The present invention allows the two quadrature signals to be acquired as a single signal, precombined at the RF level within the coil interface, or as two separate RF signals by two of the receivers of the phased array hardware. It also provides a means for remote selection of the mode of operation from the operator""s console when the system is used with a MRI system, such as the GEMS Signa system.